package wireproto

import (
	`encoding/binary`
)

var (
	// IndentChars is used when rendering a Model; it indicates the leading indent.
	IndentChars string = IndentDefault
	// SeparatorChars is used when rendering a Model; it indicates the separation between the value and the comment.
	SeparatorChars string = SeparatorDefault
)

const (
	// IndentDefault is the [IndentChars] to use if not specified.
	IndentDefault    string = "\t"
	// SeperatorDefault is the [SeperatorChars] to use if not specified.
	SeparatorDefault string = "   "
	maxByteLine      int    = 12 // (Split a hex string in a Model if a value is more than this number of bytes.)
)

// Default indent levels.
const (
	indentR uint = iota
	indentRG
	indentRec
	indentKvp
)
const indentOrigRec uint = 2

const (
	// ProtoVersion specifies the protocol version for the specification of a [Message].
	ProtoVersion uint32 = 1
)

const (
	// PackedNumSize is the size (length of bytes) of a packed unsigned integer.
	PackedNumSize int = 4 // (They're all uint32's.)
	// CksumPackedSize is the size (length of bytes) of the checksum algorithm used.
	CksumPackedSize int = 4 // CRC32 is represented by a big-endian uint32, but if a different algo is used, this will need to be changed.
)

// See https://square-r00t.net/ascii.html for further details on ASCII symbols.
const (
	AsciiNUL uint8 = iota // 0x00
	AsciiSOH              // 0x01
	AsciiSTX              // 0x02
	AsciiETX              // 0x03
	AsciiEOT              // 0x04
	AsciiENQ              // 0x05
	AsciiACK              // 0x06
	AsciiBEL              // 0x07
	AsciiBS               // 0x08
	AsciiHT               // 0x09
	AsciiLF               // 0x0a
	AsciiVT               // 0x0b
	AsciiFF               // 0x0c
	AsciiCR               // 0x0d
	AsciiSO               // 0x0e
	AsciiSI               // 0x0f
	AsciiDLE              // 0x10
	AsciiDC1              // 0x11
	AsciiDC2              // 0x12
	AsciiDC3              // 0x13
	AsciiDC4              // 0x14
	AsciiNAK              // 0x15
	AsciiSYN              // 0x16
	AsciiETB              // 0x17
	AsciiCAN              // 0x18
	AsciiEM               // 0x19
	AsciiSUB              // 0x1a
	AsciiESC              // 0x1b
	AsciiFS               // 0x1c
	AsciiGS               // 0x1d
	AsciiRS               // 0x1e
	AsciiUS               // 0x1f
)

// Response Status indicator bytes.
const (
	RespStatusByteOK  uint8 = AsciiACK
	RespStatusByteErr       = AsciiNAK
)

var (
	byteOrder binary.ByteOrder = binary.BigEndian
)

var (
	respStatusOK  []byte = []byte{RespStatusByteOK}
	respStatusErr []byte = []byte{RespStatusByteErr}
	// hdrCKSUM *must* be *exactly* as long as hdrMSGSTART and *must not* match hdrMSGSTART.
	hdrCKSUM     []byte = []byte{AsciiESC}
	hdrMSGSTART  []byte = []byte{AsciiSOH}
	hdrBODYSTART []byte = []byte{AsciiSTX}
	hdrBODYEND   []byte = []byte{AsciiETX}
	hdrMSGEND    []byte = []byte{AsciiEOT}
	endSeq       []byte = []byte{AsciiETX, AsciiEOT}
)

const (
	// WriteChunkSize is the default size of chunking to use (in bytes) when using chunked Write* functions (i.e. non-segmented).
	WriteChunkSize int = 1024
)